#
def sayHello(name):
    if name == None:
        print("Param invalid name is None")
    elif name == "gaowen":
        print("Hello VIP , " + name)
    else:
        print("Hello , " + name)


# calculate Area function
def area(width, height):
    return width * height


sayHello("gaowen")
sayHello(None)

print("area is " + str(area(5, 4)))



